1. Technical Field
The present disclosure relates to methods for making liquid crystal display modules, particularly to a method for making a liquid crystal display module with touch sensing capability.
2. Description of Related Art
A conventional liquid crystal display module for a liquid crystal display (LCD), according to the prior art, generally includes a first polarizer, a thin film transistor panel, a first alignment layer, a liquid crystal layer, a second alignment layer, a common electrode layer (e.g., an indium tin oxide (ITO) layer), an upper board, and a second polarizer. The TFT panel includes a plurality of pixel electrodes. The polarizing directions of the first and second polarizer are perpendicular to each other. When a voltage is applied between the pixel electrode and the common electrode layer, the liquid crystal molecules in the liquid crystal layer between the first alignment layer and the second alignment layer align along a same direction to make the light beams polarized by the first polarizer irradiate on the second polarizer directly without rotation. The polarized light beams cannot pass through the first polarizer. Without a voltage applied to the pixel electrode and the common electrode layer, the polarized light beams rotated by the liquid crystal molecules can pass through the second polarizer. Selectively applying voltages between different pixel electrodes and the common electrode layer can control the on and off of different pixels, thus displaying images.
A conventional polarizing layer is made by using a transparent polymer film (e.g., PVA film) to absorb the dichroism material, and the dichroism material. The dichroism material is infiltrated into the transparent polymer film, and the transparent polymer film aligns with the dichroism material in one direction. In addition to the polarizing layer, the conventional polarizer also includes protective layers, adhesive layer, separating layer covered on two opposite surfaces of the polarizing layer. During the manufacturing of the liquid crystal display screen, the second polarizer is directly attached to a top surface of the upper board.
In recent years, there is continuous growth in the number of electronic apparatuses equipped with optically transparent touch panels in front of their respective display devices (e.g., liquid crystal display screen). The touch panel is commonly attached to the top surface of the second polarizer. However, this arrangement will increase a thickness of the electronic apparatuses. Further, the touch panel and the second polarizer are individually manufactured and assembled, which increases the complexity of the manufacturing process, and increases the cost for production.
What is needed, therefore, is to provide method for making a LCD module for solving the problem discussed above.